$A0-$A2/160-162: Real-time jiffy Clock
Updated by IRQ Interrupt approx every 1/60 of Second
Update Routine is at $F69B
Kernal-Reference:
BIT $00A0 : $AFE8
INC $A0 : $F6A5
LDA $A0 : $F6B0
LDY $A0 : $F6E2
STX $A0 : $F6B6
STY $A0 : $F6E9
CMP $A1 : $E4E7
INC $A1 : $F6A1
LDA $A1 : $F6AC $F761
LDX $A1 : $F6E0
STX $A1 : $F6B8 $F6E7
BIT $00A2 : $A908
INC $A2 : $F69D
LDA $A2 : $F6DE
STA $A2 : $F6E5
STX $A2 : $F6BA
Previous Page / Next Page